After I was unable to compile this morning I deleted my git repository and downloaded a new one, and got this error.
/home/susan/emacs/lib-src/movemail.c:296:7: warning: implicit declaration of function ‘concat’ [-Wimplicit-function-declaration]
/home/susan/emacs/lib-src/movemail.c:296:16: warning: assignment makes pointer from integer without a cast [enabled by default]
/tmp/ccBpLmch.o: In function `main':
/home/susan/emacs/lib-src/movemail.c:296: undefined reference to `concat'
collect2: ld returned 1 exit status
make: *** [movemail] Error 1
make: Leaving directory `/home/susan/emacs/lib-src'
make: *** [lib-src] Error 2